In recent years, an identification by biological information such as a face, a fingerprint, an iris is used. Especially, since facial recognition can be recognized with non-contact, and gives little load to a user, use of the facial recognition is expected to increase.
In Patent Literature 1, there is disclosed a technique to select a best image of a face for a facial recognition, after capturing an image of the face of a person by using single camera with high resolution and a plurality of cameras with low resolution. Especially, in the technique disclosed in Patent Literature 1, a region of a face is detected from an input image with high resolution that is captured by the camera with high resolution, and brightness of the plurality of cameras with low resolution is controlled based on distribution of pixel values of the region of the detected face.
[Patent Literature 1]
    Japanese Patent Kokai Publication No. 2009-134593A